twin charging makes some broad powerbands. There are a few cobras and lightnings that feed the stock supercharger with turbos and make incredible power. they say that you loose a little top end hp with that setup but the power curve is like a table from low revs through redline.
you wouldnt want to use a vortec or paxton or procharger type centrifugal supercharger because they act more like a turbo and dont have the positive displacement that the roots style superchargers have, the turbo is just there to help the supercharger breathe up top.
I want to see a whipple or kenne bell blower with nicely sized turbo on something :aigo: someone with some money please step up